Fluorinated amide compounds and their preparation

ABSTRACT

Novel fluorinated amide compounds having siloxane bonds or silalkylene bonds, when crosslinked with organic peroxides, yield fluoro-rubber having excellent chemical resistance and solvent resistance.

[0001] This invention relates to fluorinated amide compounds used in themanufacture of fluorinated rubber and a process for preparing the same.

BACKGROUND OF THE INVENTION

[0002] Prior art known fluorinated amide compounds include those of thefollowing formula (i).

[0003] Herein R¹¹ is a substituted or unsubstituted monovalenthydrocarbon group, R¹² is hydrogen or a substituted or unsubstitutedmonovalent hydrocarbon group, Q¹ is a group of the following generalformula (ii) or (iii):

[0004] wherein R¹³ is a substituted or unsubstituted divalenthydrocarbon group which may be separated by an oxygen, nitrogen and/orsilicon atom, and R¹² is as defined above,

[0005] wherein R¹⁴ and R¹⁵ each are a substituted or unsubstituteddivalent hydrocarbon group, Rf¹ is a divalent perfluoro-alkylene ordivalent perfluoropolyether group, and “a” is an integer inclusive of 0.

[0006] It would be desirable to have siloxane or silalkylenebond-bearing fluorinated amide compounds which yield fluorinated rubberhaving excellent chemical resistance and solvent resistance.

SUMMARY OF THE INVENTION

[0007] It has been found that a novel fluorinated amide compound of thegeneral formula (1) is obtained by effecting hydrosilylation reaction ofa compound of the general formula (9) with a compound of the generalformula (10), the formulae being defined later; that a fluorinatedrubber having excellent chemical resistance and solvent resistance isobtained by subjecting the fluorinated amide compound to radicalcrosslinking with the aid of an organic peroxide, for example; that whenthe fluorinated amide compound has an unsaturated bond within itsmolecule, a fluorinated rubber having excellent chemical resistance andsolvent resistance is obtained by reacting the fluorinated amidecompound with a SiH group-containing compound in the presence of aplatinum group catalyst; and that the fluorinated amide compound isotherwise applicable as a pressure-sensitive adhesive, binder, coatingor agent having excellent chemical resistance and solvent resistance.

[0008] The present invention provides a fluorinated amide compound ofthe following general formula (1).

A—(Rf—Q)_(n)—Rf—A  (1)

[0009] Herein Rf is a divalent perfluoroalkylene group C_(m)F_(2m)wherein m is an integer of 2 to 15, or a divalent perfluorooxy-alkylenegroup selected from groups of the following formulae (2), (3) and (4):

[0010] wherein X is each independently F or CF₃, p and q each are aninteger of 0 to 200, r is an integer of 2 to 6, s is an integer of 1 to6, t and u each are l or 2,

[0011] wherein X is as defined above, v and w each are an integer of 1to 100,

—CF₂CF₂—(OCF₂CF₂CF₂ )_(y)—OCF₂CF₂—  (4)

[0012] wherein y is an integer of 1 to 200.

[0013] A is a monovalent organic group of the following formula (5) or(6):

[0014] wherein R¹ is a monovalent hydrocarbon group selected from amongalkyl, cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atoms andsubstituted ones of the foregoing groups in which some or all of thehydrogen atoms are substituted with halogen atoms,

[0015] R² is hydrogen or a monovalent hydrocarbon group selected fromamong alkyl, cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atomsand substituted ones of the foregoing groups in which some or all of thehydrogen atoms are substituted with halogen atoms,

[0016] Z is a divalent organic group of the formula (7):

[0017] wherein R³ is an oxygen atom or a divalent hydrocarbon groupselected from among alkylene, cycloalkylene, arylene groups of 1 to 8carbon atoms, substituted ones of the foregoing groups in which some ofthe hydrogen atoms are substituted with halogen atoms, and combinationsof alkylene with arylene,

[0018] R⁴ is a monovalent hydrocarbon group selected from among alkyl,cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atoms and substitutedones of the foregoing groups in which some or all of the hydrogen atomsare substituted with halogen atoms,

[0019] R⁵ is a monovalent hydrocarbon group selected from among alkyl,cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atoms, aliphaticunsaturation-bearing monovalent hydrocarbon groups of 2 to 20 carbonatoms, and substituted ones of the foregoing groups in which some or allof the hydrogen atoms are substituted with halogen atoms.

[0020] Q is a divalent organic group of the following formula (8):

[0021] wherein R¹, R² and Z are as defined above. The subscript n is aninteger of at least 1.

[0022] The present invention also provides a process of preparing afluorinated amide compound of the general formula (1), comprising thestep of effecting hydrosilylation reaction of a compound of the generalformula (9) with a compound of the general formula (10):

[0023] wherein R¹ to R⁵ and Rf are as defined above.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIGS. 1, 2 and 3 are diagrams showing IR spectra of the compoundsprepared in Examples 1 , 2 and 3, respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The fluorinated amide compounds of the present invention have thefollowing general formula (1).

A—(Rf—Q)_(n)—Rf—A  (1)

[0026] Herein Rf is a divalent perfluoroalkylene grou C_(m)F_(2m)wherein m is an integer of 2 to 15, or a divalent perfluorooxyalkylenegroup selected from groups of following formulae (2), (3) and (4).

[0027] Herein X is each independently F or CF₃; p and q each are aninteger of 0 to 200, preferably 1 to 100, and p+q is preferably 2 to200; r is an integer of 2 to 6, s is an integer of 1 to 6, t and u eachare an integer of 1 or 2.

[0028] Herein X is as defined above, v and w each are an integer of 1 to100, preferably 1 to 50.

—CF₂CF₂—(OCF₂CF₂CF₂)_(y)—OCF₂CF₂—  (4)

[0029] Herein y is an integer of 1 to 200, preferably 1 to 100.

[0030] The divalent perfluoroalkylene groups may be straight or branchedand include, for example, —C₂F₄—, —C₃F₆—, —C₄F₈—, —C₆F₁₂—, —C₈F₁₆—,—C₁₀F₂₀—and —C₂F₄CF(CF₃)C₄F₈—.

[0031] Examples of suitable divalent perfluorooxyalkylene groups aregiven below.

[0032] P+q=2 to 200

[0033] p+q=2 to 200

[0034] p+q=2 to 200

[0035] p=2 to 200

[0036] v=1 to 100, w=1 to 100

[0037] v=1 to 100, w=1 to 100

[0038] y=1 to 200

[0039] In formula (1), A is a monovalent organic group of the followingformula (5) or (6).

[0040] In formulae (5) and (6), R¹ is a monovalent hydrocarbon groupselected from among alkyl, cycloalkyl, aryl, aralkyl groups of 1 to 10carbon atoms and substituted ones of the foregoing groups in which someor all of the hydrogen atoms are substituted with halogen atoms; R² ishydrogen or a monovalent hydrocarbon group selected from among alkyl,cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atoms and substitutedones of the foregoing groups in which some or all of the hydrogen atomsare substituted with halogen atoms; and Z is a divalent organic group ofthe following formula (7).

[0041] In formula (7), R³ is an oxygen atom or a divalent hydrocarbongroup selected from among alkylene, cycloalkylene, arylene groups of 1to 8 carbon atoms, substituted ones of the foregoing groups in whichsome of the hydrogen atoms are substituted with halogen atoms, andcombinations of alkylene with arylene; R⁴ is a monovalent hydrocarbongroup selected from among alkyl, cycloalkyl, aryl, aralkyl groups of 1to 10 carbon atoms and substituted ones of the foregoing groups in whichsome or all of the hydrogen atoms are substituted with halogen atoms; R⁵is a monovalent hydrocarbon group selected from among alkyl, cycloalkyl,aryl, aralkyl groups of 1 to 10 carbon atoms, aliphaticunsaturation-bearing monovalent hydrocarbon groups of 2 to 20 carbonatoms, and substituted ones of the foregoing groups in which some or allof the hydrogen atoms are substituted with halogen atoms.

[0042] Suitable monovalent hydrocarbon groups represented by R¹, R² andR⁴ include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl,isobutyl, tert-butyl, hexyl, octyl, and decyl; cycloalkyl groups such ascyclopentyl, cyclohexyl and cycloheptyl; aryl groups such as phenyl,tolyl, xylyl and naphthyl; aralkyl groups such as benzyl, phenylethyl,phenylpropyl and methylbenzyl; and substituted ones of the foregoinggroups in which some or all of the hydrogen atoms are substituted withhalogen atoms, such as chloromethyl, chloropropyl, bromoethyl andtrifluoropropyl.

[0043] Examples of the alkyl, cycloalkyl, aryl and aralkyl groups of 1to 10 carbon atoms and halogenated ones thereof represented by R⁵ arethe same as enumerated above.

[0044] Examples of the aliphatic unsaturation-bearing monovalenthydrocarbon groups represented by R⁵ are vinyl, propenyl, isopropenyl,butuenyl, isobutenyl, exenyl, cyclohexenyl, and groups of the followingstructures (wherein Si is depicted for indicating the position at whichthe structure is bonded to silicon), and substituted ones of theforegoing groups in which some or all of the hydrogen atoms aresubstituted with halogen atoms.

[0045] R³ is an oxygen atom or a divalent hydrocarbon group of 1 to 8carbon atoms. Examples of the divalent hydrocarbon group represented byR³ include alkylene groups such as methylene, ethylene, propylene,methylethylene, butylene, and hexamethylene; cycloalkylene groups suchas cyclohexylene; arylene groups such as phenylene, tolylene andxylylene; substituted ones of the foregoing groups in which some of thehydrogen atoms are substituted with halogen atoms; and combinations ofalkylene with arylene.

[0046] Again in formula (1), Q is a divalent organic group of thefollowing formula (8).

[0047] Herein R¹, R² and Z are as defined above.

[0048] In formula (1), n is an integer of at least 1, preferably 2 to200, more preferably 5 to 100, and most preferably 8 to 80. Accordingly,the compound of formula (1) preferably has a number average molecularweight (Mn) of about 20,000 to 2,000,000, and more preferably 50,000 to1,000,000, and a kinematic viscosity of about 2 to 100 mm²/s ,especially about 10 to 50 mm²/s in a 10 wt % solution thereof innonafluorobutyl methyl ether (C₄F₉OCH₃).

[0049] The fluorinated amide compound of formula (1) according to theinvention can be prepared by reacting a compound of the general formula(9) with a compound of the general formula (10) in the presence of ahydrosilylation reaction catalyst.

[0050] Herein R¹ to R⁵ and Rf are as defined above.

[0051] A reaction proportion between the compound of formula (9) and thecompound of formula (10) is desirably set to a molar ratio (9)/(10) offrom 2/3 to 3/2, and most desirably a molar ratio (9)/(10) close to 1/1.

[0052] The hydrosilylation reaction catalysts used herein are preferablytransition metals, for example, platinum group metals such as Pt, Rh andPd and transition metal compounds.

[0053] Since these compounds are generally noble metal compounds whichare expensive, platinum compounds are often used because of ease ofavailability.

[0054] Exemplary platinum compounds include, but are not limitedthereto, chloroplatinic acid, complexes of chloroplatinic acid witholefins such as ethylene, complexes of chloroplatinic acid with alcoholsor vinylsiloxanes, and platinum on silica, alumina or carbon.

[0055] Suitable platinum group metal compounds other than platinumcompounds include rhodium, ruthenium, iridium and palladium compoundssuch as RhCl(PPh₃)₃, RhCl(CO)(PPh₃)₂, RhCl(C₂H₄)₂, Ru₃(CO)₁₂,IrCl(CO)(PPh₃)₂, and Pd(PPh₃)₄ wherein Ph stands for phenyl. The amountof the catalyst used is not critical and is preferably determined fromthe standpoints of economy and effective reaction so as to provide 0.1to 1,000 ppm, more preferably 0.1 to 500 ppm of platinum group metalbased on the weight of the reactants combined.

[0056] The reaction temperature may be in the range of 0 to 200° C., andpreferably 50 to 150° C. The reaction time varies over a wide range andis usually about 5 minutes to 2 hours.

[0057] The reaction may be carried out in a diluted state using anorganic solvent as long as the solvent does not adversely affecthydrosilylation. The organic solvent, if used, is preferably a partiallyor entirely fluorine-modified organic solvent.

[0058] As understood from the foregoing description, the fluorinatedamide compound obtained by the above process is terminated with an endgroup of formula (11) or (12).

CH₂═CH—  (11)

H—Z—CH₂CH₂—  (12)

[0059] Most often, these end groups of formulae (11) and (12) areadmixed at the terminus of the resulting compound. Particularly when thecompounds of formulae (9) and (10) are reacted in equimolar amounts, theend groups of formulae (11) and (12) are admixed in an equimolar stateat the terminus of the resulting compound, but in trace amounts whichare undetectable by ordinary analysis means such as IR and NMR.

[0060] By combining the fluorinated amide compound of the invention witha crosslinking agent such as an organic peroxide for inducing radicalcrosslinking, a rubber having good chemical resistance and solventresistance is obtained. When the fluorinated amide compound has anunsaturated bond within its molecule, a fluorinated rubber havingexcellent chemical resistance and solvent resistance is obtained byreacting the fluorinated amide compound with a SiH group-containingcompound in the presence of a platinum group catalyst. Moreover, thefluorinated amide compound is applicable as a pressure-sensitiveadhesive, binuer, coating or other agent having excellent chemicalresistance and solvent resistance.

EXAMPLE

[0061] Examples of the invention are given below by way of illustrationand not by way of limitation. Me is methyl, and Ph is phenyl.

Example 1

[0062] A 300-ml separable flask equipped with a stirrer, thermometer,Dimroth condenser and dropping funnel was charged with 100.0 g of acompound of formula (13) shown below (vinyl convent=0.0122 mol/100 g),100.0 g of 1,3-bistrifluoromethylbenzene, and 3.34 g of a compound offormula (14) shown below, which were homogeneously dissolved. To theflask, 0.10 g of a toluene solution of a catalyst in the form ofchloroplatinic acid modified with CH₂═CHSiMe₂OSiMe₂CH═CH₂ (platinumconcentration 0.5 wt %) was added dropwise. With stirring, reaction wasconducted for one hour at 100° C. The reaction solution was stripped forabout 2 hours under conditions: 160° C./5 mmHg, distilling off thereaction solvent. Subsequent cooling to room temperature yielded 103.3 gof a pale yellow clear gum-like compound. On analysis of the compound by¹H-NMR (TMS standard), Si—CH═CH₂ and Si—H groups were below thedetection limit. The ¹H—NMR (TMS standard) analysis confirmed thepresence of Si—CH₃ (0.17 ppm), N—CH₃ (3.35 ppm), CF₂CH═CH₂ (5.7-6.1ppm), and N—Ph—Si (7.0-7.6 ppm). An IR analysis (FIG. 1) revealed theabsorption peak associated with C═O at 1690 cm⁻¹. From these analysisresults, the compound was identified to be a polymer comprisingrecurring units of formula (15) shown below. A 10 wt % solution of thecompound in nonafluorobutyl methyl ether (C₄F₉OCH₃) showed a kinematicviscosity of 18.3 mm²/s.

Example 2

[0063] A 300-ml separable flask equipped with a stirrer, thermometer,Dimroth condenser and dropping funnel was charged with 100.0 g of acompound of formula (13) (vinyl convent=0.0122 mol/100 g), 100.0 g of1,3-bistrifluoro-methylbenzene, and 1.25 g of a compound of formula (16)shown below, which were homogeneously dissolved. To the flask, 0.10 g ofa toluene solution of a catalyst in the form of chloroplatinic acidmodified with CH₂═CHSiMe₂OSiMe₂CH═CH₂ (platinum concentration 0.5 wt %)was added dropwise. With stirring, reaction was conducted for one hourat 100° C. The reaction solution was stripped for about 2 hours underconditions: 160° C./5 mmHg, distilling off the reaction solvent.Subsequent cooling to room temperature yielded 101.2 g of a pale yellowclear gum-like compound. On analysis of the compound by ¹H-NMR (TMSstandard), Si—CH═CH₂ and Si—H groups were below the detection limit. The¹H—NMR (TMS standard) analysis confirmed the presence on Si—CH₂—Si(—0.19 ppm), Si—CH₁₃ (0.17 ppm), N—CH₃ (3.35 ppm), and N—Ph—Si (7.0-7.6ppm). An IR analysis (FIG. 2) revealed the absorption peak associatedwith C═O at 1690 cm⁻¹. From these analysis results, the compound wasidentified to be a polymer comprising recurring units of formula (17)shown below. A 10 wt % solution of the compound in nonafluorobutylmethyl ether (C₄F₉OCH₃) showed a kinematic viscosity of 12.8 mm²/s.

Example 3

[0064] A 300-ml separable flask equipped with a stirrer, thermometer,Dimroth condenser and dropping funnel was charged with 100.0 g of acompound of formula (13) (vinyl convent=0.0122 mol/100 g), 100.0 g of1,3-bistrifluoro-methylbenzene, and 4.05 g of a compound of formula (18)shown below, which were homogeneously dissolved. To the flask, 0.10 g ofa toluene solution of a catalyst in the form of chloroplatinic acidmodified with CH₂═CHSiMe₂OSiMe₂CH═CH₂ (platinum concentration 0.5 wt %)was added dropwise. With stirring, reaction was conducted for one hourat 100° C. The reaction solution was stripped for about 2 hours underconditions: 160° C./5 mmHg, distilling off the reaction solvent.Subsequent cooling to room temperature yielded 104.0 g of a pale yellowclear gum-like compound. On analysis of the compound by ¹H—NMR (TMSstandard), Si—CH═CH₂ and Si—H groups were below the detection limit. The¹H—NMR (TMS standard) analysis confirmed the presence of Si—CH₃ (0.17ppm), N—CH₃ (3.35 ppm), and N—Ph—Si (7.0-7.6 ppm). An IR analysis (FIG.3) revealed the absorption associated with C═O at 1690 cm⁻¹.

[0065] From these analysis results, the compound was identified to be apolymer comprising recurring units of formula (19) shown below. A 10 wt% solution of the compound in nonafluorobutyl methyl ether (C₄F₉OCH₃)showed a kinematic viscosity of 15.6 mm²/s.

[0066] There have been described fluorinated amide compounds havingsiloxane bonds or silalkylene bonds, which yield rubber having excellentchemical resistance and solvent resistance.

[0067] Japanese Patent Application No. 2001-245891 is incorporatedherein by reference.

[0068] Although some preferred embodiments have been described, manymodifications and variations may be made thereto in light of the aboveteachings. It is therefore to be understood that the invention may bepracticed otherwise than as specifically described without departingfrom the

1. A fluorinated aide compound of the following general formula (1):A—(Rf—Q)_(n)—Rf—A  (1) wherein Rf is a divalent perfluoroalkylene groupC_(m)F_(2m) wherein m is an integer of 2 to 15, or a divalentperfluorooxyalkylene group selected from groups of the followingformulae (2), (3) and (4):

wherein X is each independently F or CF₃, p and q each are an integer of0 to 200, r is an integer of 2 to 6, s is an integer of 1 to 6, t and ueach are 1 or 2,

wherein X is as defined above, v and w each are an integer of 1 to 100,—CF₂CF₂—(OCF₂CF₂CF₂)_(y)—OCF₂CF₂—  (4) wherein y is an integer of 1 to200, A is a monovalent organic group of the following formula (5) or(6):

wherein R¹ is a monovalent hydrocarbon group selected from the groupconsisting of alkyl, cycloalkyl, aryl, aralkyl groups of 1 to 10 carbonatoms and substituted ones of the foregoing groups in which some or allof the hydrogen atoms are substituted with halogen atoms, R² is hydrogenor a monovalent hydrocarbon group selected from the group consisting ofalkyl, cycloalkyl, aryl, aralkyl groups of 1 to 10 carbon atoms andsubstituted ones of the foregoing groups in which some or all of thehydrogen atoms are substituted with halogen atoms, Z is a divalentorganic group of the following formula (7):

wherein R³ is an oxygen atom or a divalent hydrocarbon group selectedfrom the group consisting of alkylene, cycloalkylene, arylene groups of1 to 8 carbon atoms, substituted ones of the foregoing groups in whichsome of the hydrogen atoms are substituted with halogen atoms, andcombinations of alkylene with arylene, R⁴ is a monovalent hydrocarbongroup selected from the group consisting of alkyl, cycloalkyl, aryl,aralkyl groups of 1 to 10 carbon atoms and substituted ones of theforegoing groups in which some or all of the hydrogen atoms aresubstituted with halogen atoms, R⁵ is a monovalent hydrocarbon groupselected from the group consisting of alkyl, cycloalkyl, aryl, aralkylgroups of 1 to 10 carbon atoms, aliphatic unsaturation-bearingmonovalent hydrocarbon groups of 2 to 20 carbon atoms, and substitutedones of the foregoing groups in which some or all of the hydrogen atomsare substituted with halogen atoms, Q is a divalent organic group of thefollowing formula (8):

wherein R¹, R² and Z are as defined above, and n is an integer of atleast
 1. 2. A process of preparing a fluorinated amide compound of thegeneral formula (1) as set forth in claim 1, comprising the step ofeffecting hydrosilylation reaction of a compound of the general formula(9) with a compound of the general formula (10):

wherein R¹ to R⁵ and Rf are as defined above.